Wrench



F. M. 8v J. WIRTZ.

WRENCH.

(No Model.)

No. 429,553.v PatentedJune s, 1890,

Ztzetes: y .3m um afi 72M UNITED STATES 'PATENT OEEICE.

l FREDERICK M. VIRTZ'ANDJOHANN WIR'IZ, OF COLUMBUS, OHIO.v

WRENCH.

SPECIFICATION forming part of Letters Patent No. 429,553, dated June 3, 1890.

Application filed March 28,1890. Serial No. 345 ,696. (No model.)

To all whom it may concern:

Be it known that we, FREDERICK M. WIRTZ and JOHANN WIRTZ, citizens of the United States, residing at Columbus, in the county of Franklin and State of Ohio, have invented certain new and useful Improvements in Wrenches; and we do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

Our invention relates to that class of wrenches which operate with an automatic grip.

Our present invention consists in certain novel combinations and arrangements of parts in a wrench, whereby the wrench can be instantly and automatically applie'i to nuts or screw-heads of different sizes, and the grip upon said nut or screw-head .tightened -in the operation of forcing the screw, and

when desired quickly and automatically released from the same, as will be hereinafter described.

In the accompanying drawings, Figure l is a side elevation of our improved wrench in open position. Fig. 2 is a rear elevation of the same; and Fig. 3 is a side elevation of the same, showingits jaws closed upon a small screw-head.

The letter A in the drawings represents a handle; B, au upper and C a lower jaw, and D a link.

The handle A consists of an ordinary handle portion proper d and a forked head a', which terminates with an outward Curve in the form of two branches d2 a2. The jaw C is pivoted at c to the branches c2, the pivot standing about in line with the handle. The jaw B is pivoted near its rear and upper termination at b to the link D, and the link D is pivoted at CZ to the end portions of the branches a2. The jaw B is provided with a shank b', which stands at an angle to the jaw, and is provided with a longitudinal slot b2, by means of which the shank can slide upon the pivot c. 'For this latter purpose the jaw C is provided with a niortised slot, (shown by dotted lines at c,) into which the shank h is snugly fitted, so that it can slide therein with ease, but without moving laterally. From this construction it is obvious that by turning the link outwardly or upwardly, so as to increase the distance of the pivots b and c, the jaws are gradually opened untilA the end portions b3 of the slot b2 comes in contact with the pivot c, and thus limits any further opening of the jaws. This opening may be instantaneously effected by giving an outward thrust to the wrench by means of the handle, or the same result mayl be accomplished by simply bearing down upon the nut or screw-head toV be turned with jaw B and the operator drawing the wrench toward him. Thus opened, the wrench is applied on the screw-head or not, and by pushing the jaw C against the same the jaw will yield by turning on its pivot c, and there by cause the shank b and jaw B to swing around with it, while the link D draws the jaw B toward the jaw C, thus closing the grip upon the screw-head E, as shown in Fig. 3. By turning the handle toward the jawsthe resistance of the screw-head causes the jaw C to continue to yield toward the handle and tighten the bite of the jaw B until the screw-head loosens'and is turned in the desired way.

In order to disengage the wrench from the screw-head, it is only necessary to turn the wrench backward, whereby the jaw B is moved away from the jaw C and the grip is loosened. As the resistance of the screwhead or nut increases, the grip of the jaws B C increases also, so that the inconvenience and annoyance of the wrench giving away and slipping over the corners of the screwhead ornut are avoided. Asthe resistance of the screw-head or nut diminishes, the grip of the jaws B C diminishes at the same rate, and

the wrench is thus gradually relieved of the strain upon its parts until the said resistance ceases entirely.

WVhat we claim as our invention is- The within-described wrench, combining the handle A, jaw B, and jaw C, the said jaw B being provided with a guide-shank b and connected to vthe handle by a link D and pivots b CZ, and the said jaw C being fitted to slide over the said shank and connected by' pivot c to the lever and the shank, substantially as described.

In testimony whereof we hereunto aiiix our signatures in presence of two witnesses.

FREDERICK M. IVIRTZ. JOHANN IVIRTZ.

Vitnessesz LAWRENCE DERsoM, LAWRENCE BAs'r.

IOO 

